The invention concerns wheel assemblies for industrial trolley carts as of a type commonly used in the automotive industry.
Ball bearings are widely used for wheels used in conveyor trolley carts which hold automobile bodies during the assembly process. In current designs, an axle shaft is swaged to an inner bearing race acting as a wheel hub in a design, such design is in wide use in the industry. Sometimes the swaging fails under the demanding service conditions encountered, and the axle shaft turns in the inner race, leading to bearing failure. The wheels must support heavy loads and often operate in harsh environments, but the wheel bearings desirably should operate very reliably under heavy loading over long service periods to avoid costly disruptions to the production process.
It is the object of the present invention to provide a heavy duty wheel assembly suitable for use in this application which very reliable and has a very long service life.
The present invention comprises a wheel assembly including an axle having a much more durable non-rotative connection between the axle shaft and an inner bearing race acting as a wheel hub in the current design. One end of the axle shaft has a hex shape machined on one end, slidably received in a complementary non-round hex opening in the inner race acting as a wheel hub of a first wheel assembly. A heavy duty bolt is received in a threaded bore extending axially into the end of the axle shaft. A series of roll pin holes are drilled axially into the hub outside face located so that at least one hole lies adjacent one side of the bolt hex head. A roll pin is inserted after the bolt is installed protruding to prevent the bolt from unscrewing.
An outer race/wheel is assembled over the hub and ball bearings loaded into the intervening annular space through a scallop on the outer race/wheel, and also on the inner race hub. A retainer ring is pressed onto a diameter of the hub to secure the balls.
A tee head at the opposite end of the shaft is received in a recess in the outside face of a hub of a second wheel assembly to establish a positive rotational connection between the axle and the hub-inner race of a second wheel assembly.